224 SEVENTH REPORT—1837. 
may mention, that in some few places a schistose structure 
was met with, but its extent was limited to a few yards; the 
lamellze were vertical, from an inch to three inches in thickness, 
being perfect tables, with parallel bounding planes. ‘The rock 
in which this structure occurs is a simple, indurated, gray 
clay, which flies into fragments under slight blows from the 
hammer. At Dytneh, near Serroor, some very perfect speci- 
mens have led the inhabitants to connect mystic influences with 
so artificial a development of inorganic-matter. The spot is 
daubed:- with oil and red lead, and venerated. 
Basalt en Boules.—Another characteristic feature, is the 
general diffusion of those rounded or oval masses of compact 
basalt, with concentric layers like the coats ofan onion, which 
the French geologists denominate Basalt en Boules, and our- 
selves, nodular basalt*. 
Dykes.—I now pass to the basaltic dykes, several of which 
came under my notice in different parts of the country. They 
are all vertical, and I did not observe that they occasioned any 
disturbance or dislocation in the strata of basalt and amyg- 
daloid, through which they passed. 
The gentlemen whose geological memoirs I have quoted, 
rarely advert to the subject of trap dykes, and their notices 
are very brief. Captain Dangerfield says, ‘The trap of the 
southern boundary of Malwa is much intersected by vertical 
veins of quartz, or narrow seams of a more compact heavy 
basalt, which appears to radiate from centres.” Beyond the 
continuous trap region of the peninsula, Dr. Voysey notices 
a basaltic vein in syenite, near the Cavary river at Se- 
ringapatam, which must have been propelled upwards, as it 
broke through an oblique seam of hornblende in the syenite, 
and carried the pieces up above the level of the hornblende 
vein. ‘On the eastern coast,” Mr. Calder says, ‘from Con- 
dapilli northward, the granite is often penetrated, and, ap- 
parently, heaved up by injected veins or masses of trap and 
dykes of green stone.” 
Ferruginous Clay.—The next distinctive feature is the 
* Dr. Voysey says, “The nodular wachen or basalt is one of the most 
common forms of trap in the extensive districts composed of the rocks of the 
family south of the Nermada (Nerbuddah) river. It occurs perpetually in the 
extensive and lofty range of mountains (the Gawalghur) situated between the 
Purna and Tapti rivers, and appears to form their principal mass. It is found 
equally abundant throughout the whole of Berar, part of the provinces of 
Hyderabad, Beder, and Sholapoor, and appears to form the basis of the great 
western range of trap hills which separate the Konkun from the interior of the 
Dukhun,”—Physical Class, Asiatic Researches, pp. 126, 189. 
